TNS, a computer model for predicting the temporal and spatial distribution of train noise in underground stations, is developed. The train is regarded as a series of sections, and the train noise distribution in a station is calculated by inputting the sound attenuation from a train section source in the underground system (i.e., the station and tunnel). This input can be obtained by physical scale modelling. The prediction by TNS in an underground station in London shows good agreement with site measurements. A series of computations in the station demonstrates that: (1) the overall level of the train noise in the area near the end walls is slightly less than the other areas; (2) some conventional architectural acoustic treatments in the station are effective when a train is still in the tunnel but not as helpul when the train is already in the station; and (3) train noise has a significant effect on the speech intelligibility of public address systems as measured by the Speech Transmission Index (STI). (C) 1995 Academic Press Limited [References: 19]
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